Automatic weighing machine



Dec. 7, 1943. J CLIFFORD 2,336,347

AUTOMATI C WEIGHING MACHINE Filed May 31, 1940 5 SheetSQSheet l Jay/v PC4. Fro/e0 7, 1943. J. P. CLIFFORD AUTOMATIC WEIGHING MACHINE 5Sheets-Sheet 2 Filed May 31, 1940 JOHN P CZ/F'FORD Dec. 7, 1943. J. P.CLIFFORD I AUTOMATIC WEIGHING MACHINE Filed May 31, 1940 5 Sheets-Sheet3 I a, I 1

e/OHN PCl/Froea lllll u l lhllllf l-IQ 7, 1943. J. P. CLIFFORD AUTOMATICWEIGHING MACHINE Filed May 31, 1940 '5 Sheets-Sheet 4 7,1 3 J. P;CLIFFORD AUTOMATIC WEIGHING MACHINE Filed May 31, 1940 5 Sheets-Sheet 5Jo/1W P C1. lFFORD Patented Dec. 7, 1943 AUTOMATIC WEIGHING MACHINE JohnP. Clifiord, Passaic, N. .L, assignor to Richardson Scale Company,Clifton, N. J., a corporation of New Jersey Application May 31, 1940,Serial No. 338,267

17 Claims.

The present invention relates to weighing machines, and more especiallyto those of the automatic type embodying means governed by the weighingmechanism for controlling the feed of material to a weigh hopper orother suitable weighing receptacle to make up predetermined weighedloads therein, and for controlling the discharge of the Weighed loads.The invention is applicable to machines for weighing coal, grain, flour,ore, rock products or other fluent materials of various kinds.

Heretoiore, weighing machines have been either of type employing aleverage system embodying a weighted beam which is brought to a truebalance to correctly weigh a load, and must be brought to a stop, up ordown, if out of balance, or of a type employing a dial scale and apendulum or spring action which is in equilibrium with the load at alltimes within its capacity, without resting on a stop at any time. Forthe automatic control of the materials being weighed, the balanced beamsystem possesses the advantage of the con istent action of a free beamat the time it reaches a condition of equilibrium with the load, but itsdisadvantage is its inability to indicate the condition of a weighingoperation except at the end of the cycle or When a balance is reached;and the advantage of the dial and pendulum or spring type is its abilityto indicate the condition of the weighing operation at any time duringthe cycle, but it has the disadvantage of inconsistency of the beamaction caused by the pendulum spring, which is detrimental to theautomatic control of the weighing operation.

The primary object of the present invention is to provide an improvedautomatic weighing mechanism which possesses the advantages of both ofthose systems but overcomes the disadvantages thereof. To accomplishthese results, the present invention provides a duplex beam system inwhich one of the beams, which is separate and distinct from the otherbeam which performs the weighoperation, indicates automatically at everycycle an empty condition of the weigh hopper and cont ols the initiationof the feeding of material, and t e other beam, which controls theweighing on and indicates completion thereof, does not move until thefull weighing for which it is set is made and a balanced conditionobtains.

Another object of the invention is to provide and improved means,governed by such a system for automatically controlling the ng of thematerial being weighed and the discharging the weighed loads wherebythese operations are controlled without influencing the free balancingof the beams when the weigh hopper is empty and when it contains a fullweighing, thereby insuring accuracy in the weighing operations.

Further objects of the present invention are to provide means forchecking and indicating the tare load balance by the duplex beam system,to provide novel and improved means to compensate for the weight of thecolumn of material falling into the weigh hopper at the moment the feedof material thereto is cut off, to provide a novel and improvedinterlock to prevent feeding of material into the weigh. hopper unlessthe discharge door thereof is closed, and to provide a generallyimproved control system for the various elements of the weighingmechanism whereby improved and more reliable operation is attained.

To these and other ends, the invention consists in certain improvementsand combinations and arrangements of parts all as will be hereinaftermore fully described, the features of novelty being pointed out moreparticularly in the claims at the end of this specification.

In the accompanying drawings:

Fig. l is an elevation, partly broken away, of an automatic weighingmachine constructed in accordance with the present invention;

Fig. 2 is a top plan view of the machine shown in Fig. 1;

Fig. 3 is an end elevation of the machine as viewed from the right inFig, 1;

Fig. 4 is an elevation on an enlarged scale, showing the preferreddetails of construction of the system of weighing levers and theautomatic means governed thereby for controlling the weighingoperations;

Fig. 5 is a vertical section taken on the line 5-5 in Fig. 4;

Fig. 6 is a horizontal section taken on the line 66 in Fig. 4;

Figs. 7, 8, 9 and 10 are diagrammatic views, illustrating the cycle ofoperation of the weighing mechanism;

Fig. 11 is an electrical diagram showing the conections between theelements of the automatic controlling means; and

Fig. 12 is a detail view of one of the controlling switches.

Similar parts are designated by the same reference characters in thedifferent figures.

The preferred embodiment of a Weighing machine adapted for the feedingand weighing of coal, grain, flour, ore, rock products and similarfluent materials is disclosed in the drawings and will be hereinafterdescribed in detail. It is to be understood however that the inventionis not restricted to the precise construction shown since the inventionmay be adapted to the feeding and weighing of other materials, andconstructions equivalent to that shown are contemplated and such will beincluded within the scope of the claims.

As shown in the present instance, the machine comprises generally acasing l of sheet metal or the like provided with a frame 2 of channeliron or other suitable structure for supporting it, a chute 3 throughwhich the material to be weighed is fed to the machine from a bin orother suitable source of supply, the chute being connected to the top ofthe casing preferably by a flexible dust-proof sleeve 4, a feeder 5, anda weigh hopper or other suitable weighing container 6 into which thematerial is fed and in which it is weighed, the side of the weigh hopperadjacent to the discharge end of the feeder 5 being partially cut awayand the feeder projecting partially into the weigh hopper, as indicatedin Fig. 1.

Feeders of different kinds may be employed to suit the character of thematerial to be weighed, the feeder shown in the present instance comprising an endless belt which passes over a pulley l beneath a hopper 8below the chute 3 to receive material and over a pulley e at one side ofthe weigh hopper 6 to deliver the material thereto. The belt of thefeeder is driven in a direction to carry its upper side from the hopper8 toward the weigh hopper preferably by an electric motor in through aninterposed reduction gearing ll of any suitable or well known type, thereduction gearing being connected by a chain r belt l2 to a pulley orsprocket l3 on the shaft of the belt pulley 9. The motor and reductiongearing may be conveniently mounted on the frame 2.

The weigh hopper 6 is suspended in the casing from a weighing lever [Aby a pair of shackles l5 which hang from knife edges l6 on the lever il, and the latter is fulcrumed on the casing by a pair of brackets ll onwhich rest knife edges l8 on the lever It. The end of the lever [Aopposite to that from which the weigh hopper is suspended is connectedby a rod l9 to a lever 20 which is fulcrumed by its knife edges 2! onbearings 22 supported by a bracket 23 which is fixed to the underside ofa beam box 24, the latter :3

being fixed, as by frame members 25, to the front of the casing I.

The beam box contains the system of Weigh beams and mechanism governedthereby for automatically controlling the weighing operations. The beammechanism in the beam box comprises a pair of weigh beams 30 and 3|. Thebeam 30 is pivotally supported by knife edges 32 on a bearing bracket 33fixed to a wall of the beam box, and the beam 35 is pivotally supportedby knife edges 25 upon a bearing bracket 35 fixed to a wall of the beambox. The reaction to the load or weight of the weigh hopper ii and itscontents is balanced by the pull of the lever Ell on a hook 36 whichmovable freely through the bottom of the beam box, and the load or thepull of the hook 36 is split or divided between the beams 38 and 3!, thehook being pivotally connected to knife edges 3'! which are locatedbetween the ends of a freely floating lever 38 one end of which isconnected by a shackle 39 to the weigh beam 3% by knife edges 49 and Mand the other end of which is connected by a shackle 42 to the weighbeam 3! through knife edges 43 and M. A proportion of the loadtransmitted from the weigh hopper to the beam 3t is balanced by a scalepan 45 which is suspended by knife edges it from this beam, the beam 38with its balancing pan balancing the weigh hop-per 6 or the tare load.The remaining portion of the load transmitted from the weigh hopper isbalanced by the beam 3| and its balance pan 4? which is suspended fromthis beam by knife edges 48, and by a sliding poise Q9. The beam 38 withits balance pan 55 thus balances the weigh hopper 6 or the tare load,and the beam 3! with its balance pan ii and poise d9 balances the tareload plus the net load in the container or the gross load upon the scalesystem. The sliding poise 49 is adjustable on the beam 3! according tothe net weight of the material which is to be weighed in the weighhopper, and when this poise is in its zero position as shown in Fig. 4,the balance pan (ii of the beam 34 balances the proportion of the tareload of the weigh hopper which is sustained by the beam ti. The beam 3|is freely oscillatable between upper and lower relatively fixed stops5i) and 5!, it occupying a position between these stops when in balance.The beam '30 is oscillatable between upper and lower stops 52 and 53, itoccupying a position between these stops when the weigh hopper is empty,the balance pan $5 on this beam then balancing the empty weigh hopper,and when a predetermined proportion of the total load to be weighed hasbeen introduced into the weigh hopper, the beam 35 will bear against theupper relatively fixed stop 52.

The beam 38 is operatively connected, as by a rodtt, to an indicator 5%which is pivoted at 51 on a part of the casing and cooperates with asuitable scale 53 thereon, this indicator occupying a central positionon its scale when the beam 33 is in balanced position. The beam 3! isoperatively connected, as by a rod 5%, to an indicator Gil which ispivoted at 6! on the casing and cooperates with a scale 62 thereon, thisindicator occupying a central position on its scale when the beam 3! isin balanced position. If the indicator for either beam occupies aposition at either side of its central position on the respective scalewhen the weigh hopper is empty and the poise 49 .on the beam 3! is inits zero position, this will indicate that the scale system is out ofequilibrium with the weigh hopper, and appropriate correction can bemade to bring the beam system into equilibrium with the weigh hopper.Since the beam 3t will assume its balanced position when the weighhopper is empty, the indicator 58 connected to this beam will assume itsmiddle position on its scale and thus indicate the empty or tare balancecondition of the scale system automatically at the empty or dischargepoint of the complete cycle of operations, and since the indicator 663connected to the beam 35 will assume its central position on its scalewhen this beam assumes a balanced position when the net load of materialfed into the weigh hopper is in equilibrium with this beam according tothe setting of the poise d9 thereon, this indicator will indicate thebalanced condition of the scale system automatically at the full orloaded point of the cycle of the weighing operation.

The weigh beams 39 and iii govern automatically the feeding of thematerial to and discharging thereof from the weigh hopper. Preferablyand as shown in the present instance, the material is fed into the weighhopper first rapidly or with a full feed, and when the major portion ofthe load to be weighed has been fed into the weigh hopper, the feed ofthe material is reduced to a dribble flow or feed which continues untilthe full load for which the Weighing mechanism is set has been fed intothe weigh hopper, whereupon the weighed load of material is dischargedtherefrom. The present invention also provides preferably means tocompensate for the material falling from the feeder into the weighhopper at the moment the feed of material thereto is cut off, so thatthe material thus falling will make up the full and correctly wei hedload in the weigh hopper.

Accordingly, a lever 65 is pivoted at 66 on a suitable bracket Illsecured in fixed position within the beam box, one end of this leverbeing plvotally connected at 68 to a link 69 which is guided forvertical movement by a pin III thereon which slidably engages a guide'II fixed to a wall of the beam box, the upper end of the link 6?:underlying an abutment 12 carried by the shackle 39 connected to thebeam 30. While the beam 39 is in balanced position, the abutment i2 isabove the upper end of the link 69 but when the weighted end of the beamis lifted toward its upper stop 52, under the influence of the weight ofmaterial fed into the weigh hopper, the abutment 72 will descend uponthe link 69. The lever has a Weight l3 thereon which is adjustable todifferent points along this lever according to the pro-portion of theload of material to be fed into the Weigh hopper with a full flow orfeed, and when this proportion of the load of material has been fed intothe weigh hopper, the abutment it bears on the link 65 with sufilcientpressure to lift the lever 65 and its weight '63. The lever 65 isoperatively connected by a rod or link "I4 to a switch operating member'55 which is pivoted to rock on a relatively fixed pivot 15 supported inthe beam box, this member carrying a pair of mercury switches one ofwhich has a pair of contacts 11 and "I8 which are closed when the lever$5 is in its lower position, as shown in Figs. 7 and 8, and the otl orhas a pair of contacts 19 and 8!) which are closed when the lever 65 islifted, as shown in Figs. 9 and 10.

The weigh beam 3i cooperates with a compensating lever 85 which ispivoted at 86 on a bracket 8?! suitably fixed in the beam box, one endof this lever having a link 88 pivotally connected thereto, the lowerend 89 of this link ..-eing arranged to bear against the underside ofthe beam Si and the other end of the lever 85 carrying a compensatingweight 96 which is adjustable along the length of this lever so that itmay be set to compensate for the weight of the material falling into theweigh hopper from the feeder at the moment the feeder is stopped or thefeed is interrupted. The weighted end of the compensating lever isoperatively connected, as by a link 9!, to a rocker 92 which ispivotally supported at 53 on a bracket 94 which is secured in fixedposition in the beam box, this rocker carrying a suitable switch such asa mercury switch the terminals 96 and 97 of which will be in opencondition when the Weighted end of the lever 35 is lifted, and thisrocker also carries a switch, such as a mercury switch 98 the terminals9 and I559 of which will be in closed condition when the weighted end ofthe lever 35 is lifted. The compensating lever 85 is also operativelyconnected as by a link IUI, to a rocker I32 which is pivotally mountedto rock on a pivot I83 which is supported in fixed position by asuitable bracket I04 fixed in the beam box, this rocker carrying aswitch, such as a mercury switch I05 the terminals IE5 and I9! of whichare in closed condition when the weighted end of the lever 85 is lifted,and this rocker carries a switch such as a mercury switch I08 theterminals I09 and H of which are in open condition when the weighted endof the lever 85 is lifted. When the weighted end of the lever 85 islowered, the terminals of the switches 95 and I08 are in closedcondition and the terminals of the switches 98 and I95 will be in opencondition. The descent of the weighted end of the compensating lever 85is limited by a stop H which may be carried on the relatively fixedsupporting bracket 87 for the compensating lever. This stop is solocated or adjusted that the abutment 89 on the lower end of the link 88will be held out of engagement with the underside of the beam 3| as thelatter approaches its balanced position between the stops 50 and 5 I.

The weigh hopper 5 is provided with a door I which controls the dischare of the weighed load of material therefrom. Preferably and as shown,this door is pivoted at I El to the lower end of the weigh hopper sothat it may swing in a vertical plane to and from closing relation withthe open bottom of the weigh hopper, and the door is counterweighted bya weight it? which overbalances the weight of the door and acts toautomatically close the door after a load of material has beendischarged from the weigh hopper. The door is locked in its closedposition. by a toggle comprising a pair of pivotally connected linksi523 and I24, the lower end of the link I23 being pivotally connected atI 23 to the hopper door I], and the link IE4 being pivotally connectedto the adjacent side of the hopper by a pivot pin I25 to one end ofwhich a lever E25 is also pivoted, this lever being provided with a stopI27 against which the toggle link I24 rests while in locked position.The lever I25 is operatively connected at its free end to the core E28of a solenoid I29 mounted on the weigh hopper. The link I 24 operates orcarries a switch, preferably a mercury switch I which will be in aclosed circuit condition when the weigh hopper door is closed and lockedby its toggle, at which time the toggle link I2 1 will rest on the stopE27, and will be in open circuit condition while the weigh hopper dooris open, as shown in Figs. 1 and 11, this switch rocking with the togglemember I24 during the closing and opening movements of the hopper doorI28.

An example of electrical circuits for automatically controlling theoperation of the weighing machine is shown diagrammatically in Fig. 11.The diagram shown in thi figure is suitable for three hase alternatingcurrent for operating the motor which drives the feeder, the controlsbeing operated by a single phase alternating current, but is to beunderstood that the same electrical systeisubstantially as shown in thisdiagram may be used for either single phase alternating current or fordirect current.

In the diagram, Fig. 11, L, L and L represent the three lines from asuitabl source of three phase alternating current, i3! represents anelec tromagnetic relay three pairs of contacts of which, when this relayis energized, connect the power lines L L and L to the high speedwinding of the motor 5 3 which is of a two speed type, I32 represents anelectromagnetic relay three pairs of contacts of which connect, whenthis relay is energized, the line wires H, L and L to the low speedwinding of the motor I9, and I33 represents an electromagnetic relaythree pairs of contacts of which, when this relay is energized, connectthe line wires L L and L to a brake incorporated in the motor Hi, thisbrake when energized, being inoperative or permitting the motor to runfreely and when deenergized serving to stop the running of the motor.[34 represents an electromagnetic relay for releasing the weigh hopperdischarge door I20, it having two pairs of contacts which, when thisrelay is energized, connect the line wires L and L to the solenoid H29which breaks the toggle I23, I24 and releases the weigh hopper dischargedoor.

Singie phase alternating current derived from the line wires L and l.-energizes the primary of a step-down transformer I35 the secondary ofwhich is controlled by a switch i556 having terminals and H38. A circuitleads from the terminal 5 3? through the weigh hopper discharge doorswitch ltd, thence to contact 9'! of switch 95 L to contact 586 ofswitch 98, thence to contact I? of switch operating member '55, thencefrom con- ?8, through contacts 139 and MS of relay i thence through thewinding of relay [3| and to terminal l38 of switch I36. Another fromcontact 95 of switch it to contact is of switch operating member 75,thence from contact 86 of th latter switch through contacts iii and M2of relay l3! and through the windin of relay I32 and then to theterminal of switch I35. A branch circuit leads from the contact it ofswitch operating member iii to the winding of the relay H33 and throughsaid to contact E38 of switch ltd. Another switch to contact 9? ofswitch 95, then from contact of said switch through a test switch to thewinding of relay Kid, and through this winding to the terminal I38 ofswitch I36.

machine as shown is provided with a counter its for totalizing thenumber of weighmade during the period of operation. For this purpose, acounter is employed which may be of any uitable and known type, thecounter shown diagrammatically in the present instance comprising amotor 545 which operates the coun ter a half revolution, through areduction gearing, for each energization thereof and during each halfrevolution of the counter moves a cam i t5 driven by the motoralternately into positions to engage and disengage the contacts l4! andit? with a, contact Hi9 connected to one terminal of the motor M55. Thecircuit for this counter is ds from the contact I37 of switch I35 toconn to contact 238 of switch or through a nch circuit from contact 53!to contact 591, to contact ltd of switch lil5, then to contact motor N5and then to contact L38 of switch the motor circuit is closed throughthe motor is energized and rotates V through a half revolution, therebythis contact from th contact i i-d opping motor after the counter hasbeen need a half revolution the contact it? being engaged with thecontact M9, and when the motor circuit is closed through the contactMil, cam Hit makes another half revolution there- 'sengaging contact M?from contact 2 25 and .r-ping the motor after the counter has adtheother half revolution.

The operation of an automatic weighing machine constructed ashereinbefore described and shown in the drawing i as follows:

circuit leads from the hopper door discharge i As a. preliminary, themachine may be tested to determine whether the beam system is in anaccurately balanced condition when the weigh hopper is empty. This isaccomplished by setting the poise 49 at the zero mark on its beam, asshown in Fig. 4. If the weigh hopper is empty and both beams 39 and SIassume balance positions, as shown by the indicators 56 and 68respectively, the beam system is in true'balance with the tare load ofthe empty weigh hopper, the beams 35 and til then balancing, by only thebalance pans 35 and 41, respectively, the proportions of the tare loadcarried by the respective beams, the ratio of these proportionsdepending on the ratio of th floating load splitting lever or beam 38.During this test, the switch 136 in the circuit containing the automaticcontrol devices is open so that the motor l0 driving the feeder is idle,and the other switches at this time are as shown in Fig. 11.

By moving the poise it along the beam 3% to the mark representing theweight of the loads to be weighed, as for example, the 100 lb. mark, asshown in Fig. 7, the weighing mechanism is set in condition to start theWeighing cycle. Movement of the poise 59 from the zero mark throws thebeam 3| out of balance, it dropping to the lower stop 5|. As theWeighted end of the beam 3! thus descends, it engages the abutment $59on the link 88 and thereby tilts the compensating lever 85 and theswitches 95, Q8, Hi5 and hid connected to it. The compensating weight soon the lever 85 exerts an upward pull on the beam 3! which lifts itsweighted end before the weigh hopper has received its full weighing andto stop the feed of material, thus compensating for the weight ofmaterial falling ofi the discharge end of the feeder a into the weighhopper at the moment the beam 3! rises and the feed is out off.

The descent of the weighted end of the beam 33 under the action of thepoise d9 rocks the compensating lever 35 in a direction to open theswitches and l as and close the switches 98 and Hit. Since the tar beamat this time is balanced, the contacts Ti and it! will be closed and thecontacts 29 and 82! of this switch will be open. Assuming the Weighhopper door is closed, the hopper door switch will be closed and thehopper will be ready to receive a weighing. The empty balance indicatorat this time will be in its middle or zero position, showing that thetare beam 39 is balanced, and the full balance indicator fill will be ohits scale since the weigh beam it is off balance, as shown in Fig. '7.The relays IBI, I32, 133 and 34 at this time will all be tie-energized.

With the switches in the positions described, and assuming material issupplied through the chute 3 to the feeder 5 and electric current issupplied to the lines L L and L closing of the control switch l36 willstart the weighing cycle. Closing of the switch I35 supplies currentfrom its terminal 53?, through hopper door switch I30 which is thenclosed, contacts 9'! and H30 of switches and 93, closed contacts '51 andi3, contacts 539 and Id!) of relay I32 which is then ole-energized,solenoid winding of relay I31 and thence to terminal I33 of switch I35.The circuit thus completed with the secondary of transformer i35operates the relay 13! to close the line circuit from the power lines LL and L through the three pairs of contacts of this relay, to the highspeed winding of the motor IE and the latter then operates at its higherspeed to drive the feeder 5 to feed material into the weigh hopper witha full flow or feed. A branch circuit is completed at the same time fromthe contact 99 of switch 08 through the solenoid winding of relay I33and then to terminal I38 of switch I36, thereby closing the three pairsof contacts of this relay and energizing the brake of the motor I tohold the brake in inoperative condition. As the material is fed into theweigh hopper, the pull exerted on the hook 36 increases. A portion ofthis increased load is carried by the tare beam 30 which is therebythrown out of balance and is tilted until the abutment 12 on the shackleengages the top of the link 69, the beam 30 at this time however beingout of engagement with its upper stop 52. The remaining portion of theload is carried by the weigh beam 3I which, however, cannot rise to abalanced position until the additional pull on the hook is sufficient tocounterbalance the poise 49. This stage of the weighing cycle, with theweigh hopper partially filled, is shown in Fig. 8.

As the load in the weigh hopper increases under the full flow ofmaterial therein, the load transmitted by lever 38 through abutment 12to link 63 increases, and this force tends to lift the weighted end oflever 65 and thereby operate the switch operating member 15. The weight"I3 however holds lever 65 down on its stop until the load of materialfed into the weigh hopper reaches the proportion of the full weighingfor which the weight I3 is set as, for example, 80

per cent of a full weighing, When such proportion of the full weighinghas been fed into the weigh hopper, the force exerted by the abutment I2on the link 39 is sufiicient to lift the weighted end of the lever 65,thereby operating the switch operating member I3 to open the full feedcontrolling contacts T1 and I8 and to close the dribble feed controllingcontacts I9 and 80. The tare beam 33 then comes to rest against itsupper stop 52, as shown in Fig. 9.

Opening of the contacts I! and I8 breaks the circuit through thesolenoid winding of relay I3I,

thereby deenergizing it and causing its contactor to open the powercircuit to the full or higher speed winding of the motor I0 and to closethe contacts MI and I42 of this relay, and closing the contacts 19 and80 of switch I completes a circuit from terminal I31 of switch I36,through the then closed hopper door switch I30, contact 31 of switch 35,engaged contacts 90 and I00 of switch 93, engaged contacts I9 and 80,engaged contacts MI and I42 of tie-energized relay I3I,

solenoid winding of relay I32 and then to ter- I minal I33 of switchI38. Completion of this circuit operates the relay I32 to close thepower circuit from the power lines L L and L to the lower speed windingof the motor I0, through the three pairs of contacts of this relay whichwere disengaged when this relay was de-energized. A branch circuit iscompleted at the same time from the contact 99 of switch 83 through thesolenoid winding of relay I33 and then to terminal I33 of switch I33,thereby closing the three pairs of contacts of this relay and energizingthe brake of the motor I0 to hold the brake in inoperative condition.The motor It then operates the feeder 5 at its slower or dribble speed,and the remaining proportion of the full weighing, as per cent in theexample above stated, flows into the weigh hopper at such slower rate,this stage in the weighing cycle being shown in Fig. 9.

As the wei ht of material fed into the weigh hopper approaches theamount for which the poise 43 is set, a point is reached where the pullirom the lever 33 plus the lift from the link 88 attached to thecompensating lever is sulficient to raise the counterweighted end of theweigh beam 3i and drop the compensating lever 35 to its stop II5. Suchtilting of the compensating lever also tilts the switches connectedmereto, opening the contacts 99 and I00 of the dribble cut off switch 98and closing the contacts 96 and 9'! of the discharge controlling switch35, and closing the contacts I09 and IIEI oi counter operating switchI08 and opening the contacts I06 and I0? of counter operating switchOpening of the dribble switch 98 breaks the circuit through the windingof relay I32, thereby ole-energizing this relay and breaking the lowspeed power circuit from the power lines to motor I0, thus stopping thefeeder, and opening of the switch 98 also breaks the branch circuitthrough the solenoid winding of relay I33, thus ole-energizing thisrelay and breaking the line circuit tnerethrough to the brake of themotor, causing the brake to be applied to stop the motor and feeder 5.The material falling from the feeder to the weigh hopper at the instantthe feed is stopped is sufficient to bring the weigh beam 3! to abalance, and this balanced condition will be shown by the full balanceindicator as illustrated in Fig. 10.

Closing of the discharge controlling switch completes a circuit from theterminal I3! of switch I33 through the then closed hopper discharge doorswitch I30, closed contacts 96 and 31 of switch 35 through test switchI53, solenoid winding of relay I35 and then to terminal I33 of switch I33, and if the test switch is closed, as is usual during the continuousoperation of the machine, the relay I34 will be energized, closingthrough its contacts a power circuit from the power lines L and Lthrough the solenoid I29, causing the latter to break the toggle I23,I24 and thereby unlock the weigh hopper discharge door I20 toautomatically discharge the weighed load of material from the weighhopper. However, if it is desired to test the weighing for accuracy, thetest switch I43 may be left open at the beginning of the weighing sothat the load of material weighed into the weigh hopper will not beautomatically discharged therefrom but will remain therein so that theaccuracy of the balance may I be indicated. Closing of the test switchwill cause the weighed load of material to be discharged from the Weighhopper in the manner already described.

Opening of the discharge door I20 of the weigh hopper opens the hopperdischarge door switch I33, and this switch remains open as long as thehopper discharge door is not locked shut. Since this switch I30 is inseries in the circuits controlled by the switch operating member IE, andswitches 93 and 98 which govern the operation or" the feeder operatingmotor I0, no material can be fed into the weigh hopper by the feederunless the weigh hopper discharge door is closed and locked. Closing andlocking of the weigh hop per discharge door after dischargin a weighedload, however, closes the switch I30, permitting the machine to repeatits operating cycle automatically.

Discharge of each weighed load of material from the weigh hopperrestores the beams 33 and 3I and the switches governed thereby to thecon dition shown in Fig. 7, ready for the commencement automatically ofanother weighing cycle.

'Since the tare beam 30 comes. to balance when the weighed load isdischarged from the weigh hopper, its indicator will show the tarebalance condition at the empty or discharge point of each complete cycleof operations.

The dropping of the compensating lever 85 upon its stop H5 when theweighing beam 3| comes to balance during each cycle of operations closesthe counter switch I88, thereby completing a circuit from the terminalI31 of switch I36 through the closed contacts I09 and III], terminalsI41 and I49 and motor I45 to terminal I38 of switch I36, thereby causingmotor I45 to operate the counter through a half revolution and rotatethe cam M6 to disengage the contact I i? from the contact I49 and engagecontact I48 therewith, and upon discharge of the weighed load ofmaterial from the weigh hopper, the counter switch I08 is opened and thecounter switch I05 is closed, thereby completing a circuit from terminalI31 through the closed contacts I06 and H11, contact I48 and motor I45to terminal I38, thereby again energizin motor I 55 to operate thecounter through its remaining half revolution to make a count of theweighed and discharged load and rotating the cam I46 to break the motorcircuit by disengaging the switch member I48 from the contact I59 andreengaging the contact WI with contact M9 ready for the next count.

An automatic weighing machine constructed as hereinbefo're describedprovides a tare beam which is separate and distinct from the beam whichperforms the actual weighing and which may come to balance position andits balanced condition indicated after the discharge of each weighedload of material is discharged from the weigh hopper, and it provides agross weighing beam which is separate and distinct from the tare beamand which may come to balance and its balanced condition indicated whenthe full load of material has been fed into the weigh hopper, but whichdoes not move until the full weighing is made and a balanced conditionobtains.

The balancing of the tare load beam after the discharge of each weighedload of material from the weigh hopper is not influenced by the controlswitches governed by this beam so that the tare beam is free to balance,and the gross weighing beam is not influenced by the control switchesgoverned by this beam since these control switches are operated by thecompensating lever which comes to its stop before the gross weighingbeam comes to a balance, thus leaving this beam free to assume aposition which corresponds accurately with the weight of the load ofmaterial fed into the weigh hopper. Accuracy in the weighings istherefore ensued, and any adjustments that may be necessary will beindicated by the indicators for the beams during the cycles of weighingoperations.

I claim as my invention: 7 I

1. In an automatic weighing machine having a weigh hopper and means forfeeding material to and discharging it from the weigh hopper, a tarebeam and a gross weighing beam, a floating lever connected at its endsto the respective beams and connected between its ends to the weighhopper for proportionately dividing between said beams the load of theweigh hopper, said beams being separately pivoted and independentlyoperable, an indicator connected to and operable by each of said beamsfor indicating the balance position thereof, and means having lostmotion connections with and governed by said beams for automaticallycontrolling the feeding of material to and the discharging thereof fromthe weigh hopper, said beams being free of the influence of said lattermeans while in balance positions.

2. In an automatic weighin machine having a weigh hopper and means forfeeding material to and discharging it from the weigh hopper, a tarebeam and a gross weighing beam, a floating lever connected at its endsto the respective beams and connected between its ends to the weighhopper for proportionately dividin between said beams the load of theWeigh hopper, said beams being separately pivoted and independentlyoperable, an indicator connected to and operable by each of said beamsfor indicating the balance position thereof, a stop for limiting themovement of the tare beam in either direction from a balance positionunder the influence of material fed into the weigh hopper, and meanshaving lost motion connections with and governed by said beams forautomatically controlling the feeding of material to and the dischargingthereof from the weigh hopper, said beams while in balance positionsbeing free of the influence of said controlling means.

3. In an automatic weighing machine having a weigh hopper and means forfeeding material to and discharging it from the weigh hopper, a tarebeam and a gross weighing beam, a floating lever connected at its endsto the respective beams and connected between its ends to the weighhopper for proportionately dividing between said beams the load of theweigh hopper, said beams being separately pivoted and independentlyoperable, an indicator connected to and operable by each of said beamsfor indi cating the balance position thereof, means having a lost motionconnection with and governed by the tare beam for feeding material tothe weigh hopper, and means having a lost motion connection with andgoverned by the gross weighing beam independently of the tare beam forcontrolling the discharge of material from the weigh hopper.

l. In an automatic weighing machine having a weigh hopper and means forfeeding material to and discharging it from the weigh hopper, a tarebeam and a gross weighing beam having means for proportionately dividingbetween them the load of the weigh hopper, said beams being separatelypivoted and independently operable, an indicator connected to andoperable by each of said beams for indicating the balance positionthereof, means governed by the tare beam for feeding material to theweigh hopper first with a full feed and then with a dribble feed, andmeans governed by the gross weighing beam independently of the tare beamfor cutting oi? the dribble feed and discharging the weighed mate rialfrom the weigh hopper.

5. In an automatic weighing machine having a weigh hopper and means forfeeding material to and discharging it from the weigh hopper, a tarebeam and gross weighing beam, a floating lever connected at its ends tothe respective beams and connected between its ends to the weigh hopperfor proportionately dividing between said beams the load of the weighhopper, said beams bein separately pivoted and independently operable,an indicator connected to andoperable by each of said beams forindicating the balance position thereof,- means including a switchhaving a lost motion connection with the tare beam and operablewhile-the tare beam is in a tare balance position and free of theinfluence thereof for feeding material to the weigh hopper, and meansincluding a switch having a lost motion connection with the grossweighing beam and operable when the gross weighing beam assumes abalance position and becomes free of the influence thereof for cuttingoff the feed of material to the Weigh hopper.

6. In an automatic weighing machine having a weigh hopper and means forfeeding material to and discharging it from the weigh hopper, a tarebeam and a gross weighing beam having means for proportionately dividingbetween them the load of the weigh hopper, said beams being separatelypivoted and independently operable,

an indicator connected to and operable by each of said beams, meansincluding a switch operable while the tare beam is in a tare balanceposition and free of the influence thereof for feeding material to theweigh hopper with a full feed and for reducing the feed of material to adribble feed by movement of the tare beam out of tare balance positionwhen a predetermined proportion of the material to be weighed has beenfed into the weigh hopper, and means including a switch governed by thegross weighing beam as it approaches balance position for cutting offthe dribble feed, the gross weighing beam being free of the influence ofsaid dribble feed cutting off means while it is in balance position,

7. In an automatic weighing machine having a weigh hopper and means forfeeding material to and discharging it from the weigh hopper, a tarebeam and a gross weighing beam having means for proportionately dividingbetween them the load of the weigh hopper, said beams being separatelypivoted and independently operable, an indicator connected to andoperable by each of said beams for indicating the balance positionthereof, means including a switch operable while the tare beam is in atare balance position and free of the influence thereof for feedingmaterial to the weigh hopper with a full feed and for reducing the feedof material to a dribble feed by movement of the tare beam out of tarebalance position when a predetermined proportion of the material to beweighed has been fed into the weigh hopper, means including a switchgoverned by the gross weighing beam as it approaches balance positionfor cutting oif the dribble feed, and means including a switch governedby the gross weighing beam as it ap proaches balance position fordischarging the material from the weigh hopper, the gross weigh ing beamwhile in balance position being free of the influence of said means forcutting oif the dribble feed and said discharging means.

8. In an automatic weighing machine having a weigh hopper and means forfeeding material to and discharging it from the weigh hopper, a tarebeam and a gross Weighing beam, a floating lever connected at its endsto the respective beams and connected between its ends to the weighhopper for proportionately dividing beveen said beams the load of theweigh hopper, said beams being separately pivoted and independentlyoperable, an indicator connected to and operable by each of said beams,means including a switch having a lost motion connection with the tarebeam and operable while the tare beam is in a tare balance position forfeeding material to the weigh hopper, and means including a switch andcompensating means for the falling column of material, said switch beingconnected to said compensating means and the latter having a lost motionconnection with and being operable upon the gross weighing beam foroperating said switch to cut off the feed of material to the weighhopper, the gross weighing beam being movable beyond the influence ofsaid compensating means into a balance position.

9. In an automatic weighing machine having a weigh hopper and means fofeeding material thereto, a pair of separately pivoted distinctlyoperable beams counterweighted to proportionately support the weighhopper, means beyond the influence of one of said beams while in balanceposition for initiating the feeding of material into the weigh hopperand operable by movement of said beam out of balance position under theload of material fed into the weigh hopper for automatically reducingthe rate of feed, and means operable under control of movement of theother beam toward balance position under the load of material in theweigh hopper for automatically cutting off said feed, said other beambeing free of the influence of said latter means while in balanceposition.

10. In an automatic weighing machine having a weigh hopper and means forfeeding material to and discharging it from said hopper, separatelypivoted distinctly operable tare and gross weighing beams, the tare beambeing counterweighted to support a proportion of the weight of the weighhopper and the gross weighing beam being counterbalanced to support theremaining proportion of the weight of the weigh hopper and the netweight of a load of material to be weighed, means beyond the influenceof the tare beam while in balance position for initiating the feeding ofmaterial into the weigh hopper and operable by movement of the tare beamout of balance position under the load of material fed into the weighhopper for automatically reducing the rate of feed, and means operableunder control of movement of the gross weighing beam toward balanceposition for automatically cutting off said feed and discharging theload of material from the weigh hopper, the gross weighing beam beingfree of the influence of said feed cutting off and discharging meanswhile in balance position.

11. In an automatic weighing machine having a weigh hopper and means forfeeding material to and discharging it from said hopper, separatelypivoted distinctly operable tare and gross weighing beams, the tare beambeing counterweighted to support a proportion of the weight of the weighhopper and the gross weighing beam being counterbalanced to support theremaining proportion of the weight of the Weigh hopper and the netweight of a load of material to be weighed, means beyond the influenceof the tare beam while in balance position for initiating the feeding ofmaterial into the weigh hopper and operable by movement of the tare beamout of balance position under the load of material fed into the weighhopper for automatically reducing the rate of feed, means to compensatefor the weight of material falling into th weigh hopper when the feed iscut off, said compensating means acting on and being controlled by thegross weighing beam as it approaches balance position and said grossweighing beam being free of the influence of said compensating meanswhen it assumes balance position, and means operable by saidcompensating means to cut oif the feed of material to the weigh hopperand to discharge the weighted load of material therefrom.

12. In an automatic weighing machine having a weigh hopper and meansincluding controlling switches for feeding material to and dischargingit from the weigh hopper, a pair of separately mounted distinctlyoperable weigh beams, means for supporting the weigh hopperproportionately from said beams, one of said beams being counterweightedto balance its proportion of the tare weight of the weigh hopper, andthe other beam being ccunterweighted to balance its proportion of thetare weight of the weigh hopper and a proportion of the net weight ofthe material to be weighed, a weighted member operable as said tare beamassumes a tare balance position to actuate one of said feed controllingswitches to initiate feed of material to the weigh hopper and operableas said tare beam moves out of balance position under the influence of apredetermined proportion of the weight of the material to be weighed inthe weigh hopper to actuate a second one of said feed controllingswitches to reduce the feed of material, and a Weighted lever acting onthe other beam to compensate for the weight of the material being fedinto the weigh hopper after out on" and operable under control of saidbeam to actuate another of said feed controlling switches to cut off thefeed of material to the weigh hopper and to actuate the dischargecontrolling switch to discharge the weighed material from the weighhopper.

13. In an automatic weighing machine having a weigh hopper, meansincluding full feed and dribble feed controlling switches forcontrolling the feed of material to the weigh hopper, and meansincluding a switch for controlling the discharge of the weighed materialfrom the weigh hopper, a tare beam counterweighted to balance the weighhopper, a gross weighing beam counterweighted to balance the gross loadof the weigh hopper and the weighed material therein, a Weighted leveroperatively connected to the full feed controlling switch to close saidswitch and initiate the full feed when the tare beam assumes a balancedposition and to open said switch and stop the full feed and close thedribble feed switch to initiate the dribble feed when a predeterminedproportion of the Weight of the material acts on the tare beam, andmeans governed by the gross weighing beam for operating another of saidfeed controlling switches to cut o-fi the dribble feed and for operatingthe discharge controlling switch to discharge the Weighed material fromthe weigh hopper.

14. In an automatic weighing machine having a weigh hopper, meansincluding full feed and dribble feed controlling switches forcontrolling the feed of material to the weigh hopper, and meansincluding a switch for controlling the discharge of the weighed materialfrom the weigh hopper, a tare beam counterweighted to balance the weighhopper, a gross weighing beam counterwei hted to balance the gross loadof the weigh, hopper and the weighed material therein, a weighted leveroperatively connected to the full feed controlling switch to close saidswitch and initiate the full feed when the tare beam assumes a balanceposition and to open said switch and stop the full feed and close thedribble feed switch to initiate the dribblefeed when a predeterminedproportion of the weight of the material acts on the tare beam, aweighted compensating lever acting on the gross Weighing lever to moveit toward balance position, and means connecting the compensating leverto another of said feed controlling switches and the dischargecontrolling switch to cut off the feed of material and discharge theweighed material from the weigh hopper.

15. In an automatic weighing machine having a weigh hopper and means forfeeding material to and discharging it from said hopper, a pair ofseparately mounted and distinctly operable weigh beams havingrespectively means for balancing the Weigh hopper and the weigh hopperand a load to be weighed therein, a floating lever connected at its endsto the respective beams and connected be ween its ends to the weighhopper for supporting the weigh hopper proportionately by said beams,means controlled automatically by one of said beams to reduce the rateof feeding of the material to the weigh hopper, means controlledautomatically by said one of said beams for indicating an empty balancecondition of the weigh hopper, and means governed by the other of saidbeams for stopping the feeding of material to and discharging it fromthe weigh hopper.

16; In an automatic weighing machine having a weigh hopper and means forfeeding material to and discharging it from said hopper, a pair ofseparately mounted distinctly operable weigh beams, a floating leverconnected at its ends to the respective beams and connected between itsends to the weigh hopper for supporting the weigh hopper proportionatelyby said beams, means counterbalancing one of said beams to balance aproportion of the tare weight of the weigh hopper, means forcounterbalancing the other beam to balance another proportion of thetare weight of the weigh hopper and a proportion of the load to beweighed therein, means controlled automatically by said one of saidbeams to reduce the rate of feeding of the material to the weigh hopper,means controlled by said one of said beams for automatically indicatingan empty balance condition of the weigh hopper, and means having a lostmotion connecnection with said other beam and governed automaticallythereby for stopping the feeding of material to and discharging it fromthe weigh hopper.

7.. In an automatic weighing machine having a weigh hopper and means forfeeding material to and discharging it from said hopper, the combinationof a pair of separately mounted and separately operable weighing beams,a floating lever connected at its ends to the respective beams andconnected between its ends to the weigh hopper for supporting the weighhopper proportionately by said beams, one of said beam beingcounterbalanced to balance the tare load and the other beam beingcounterbalanced to balance the gross load, and means having lost motioncon-- nections with and governed by said beams for controlling thefeeding of material to and the discharging thereof from the weighhopper, said beams being free to swing independently in a balancedcondition Within limits set by said material controlling means, and oneof said beams oscillating with a tare balance and the other of saidbeams oscillating with a gross balance.

J OHN P. CLIFFORD.

